Field
Aspects of the present disclosure relate generally to voltage sensing, and more particularly, to voltage sensors.
Background
There is a trend to reduce the power supply voltage of mobile devices to reduce power consumption. However, lowering the power supply voltage increases the problem of voltage droop (e.g., due to power gating) and noise (e.g., due to clock switching). Voltage droop may cause logic failure in a device and/or the device to unexpectedly shut down.
In this regard, voltage sensors may be integrated on a chip to monitor the power supply voltage at various locations on the chip. The voltage readings from the sensors may be used, for example, to debug a chip by identifying voltage waveforms indicative of a failure in the chip. The voltage readings may also be used for adaptive clocking to prevent the power supply voltage from becoming too low. In this application, when the supply voltage falls below a voltage threshold, the clock frequency of a circuit (e.g., central processing unit (CPU)) may be reduced (throttled back) to increase the supply voltage. The voltage readings may also be used to verify that a model of the power distribution network (PDN) of the device is accurate.